´92 E150 brakeline problems .. cant move !
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Originally Posted by kynnhoj
JCBX,
I saw your pics in the first post and I am wondering what metal your brake lines are made of. It appears to be copper???? This is not good if that is the case. ( EXTREMELY DANGEROUS ) It sounds to me as if your van needs profesional diagnosis and repair. The liabilities of you fixing this are too great. Both for you and others on the road.
John
I saw your pics in the first post and I am wondering what metal your brake lines are made of. It appears to be copper???? This is not good if that is the case. ( EXTREMELY DANGEROUS ) It sounds to me as if your van needs profesional diagnosis and repair. The liabilities of you fixing this are too great. Both for you and others on the road.
John
this is common in EU to use this , this is the only thing you are allowed to use (I you dont use OEM lines) and this last longer than the car , and sertainly not as weak as the oem ones on my E-150 as they are rusted as h¤¤¤
also ! all Volvo and SAAB comes with copper lines from the factory ..........
when using copper you are making a double cone at the ende VS the OEM lines that had only one cone
Sincerly
JCBX
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I've never seen copper used in a brake system, except for sealing washers used between a front brake hose block, and the disc brake caliper on some cars and trucks. There, the copper washer has a large wall thickness, but short length, and it is tightly compressed by the hose block bolt.
Brake system pressures can get up near 1000 PSI (that is about 7000 kPa in Metric units) under some conditions, like a panic stop.
Brake system pressures can get up near 1000 PSI (that is about 7000 kPa in Metric units) under some conditions, like a panic stop.
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Although I don't have a van, I have worked on large Ford cars which have a similar Master Cylinder and side-mounted Proportioning Valve. The side outlet with the Proportioning Valve goes to the rear drum brakes. The front outlet goes to the front disc brakes.
In disc brakes, the braking force is directly proportional to the applied hydraulic force acting on the piston in the caliper.
In drum brakes, as the hydraulic line pressure increases, a brake force multiplying factor occurs. As the two brake shoes press outwards against the drum, they try to turn a bit with the drum. This causes the front-most brake shoe to press against the adjuster screw assembly, which then presses against the rear-most shoe. And the rear-most shoe rotates up against the anchor pin up at the top. The net effect is that the two shoes "wedge" themselves against the drum, boosting braking effort.
As you press harder on the brake pedal, the Proportioning Valve first allows full Master Cylinder pressure to go to the rear drum brakes. But as pedal pressure increases, eventually you will hit the "split point" of the Proportioning Valve. After the split point is reached, the pressure into versus pressure out of the P.V. will no longer be a 1:1 ratio. For a further increase of pedal pressure, the rear line pressure will not increase as much. This limiting the increase in rear brakeline pressure avoids premature lock-up of the rear brakes due to the self-wedging action of drum brakes.
The front disc brakes, on the other hand, continue to get direct pressure, as they always work proportionally.
When releasing the brake pedal, the P.V. unseats, and allows brake fluid to return to the Master Cylinder so the rear shoes can retract.
I looked around to see if I still have a P.V. laying around. I can't find it. I have taken them apart, little plastic pieces like that cone you smashed, tiny passages, and some fine wire springs. They are precision parts.
Ten years ago they were ~ $90 USD at a Ford dealer.
In disc brakes, the braking force is directly proportional to the applied hydraulic force acting on the piston in the caliper.
In drum brakes, as the hydraulic line pressure increases, a brake force multiplying factor occurs. As the two brake shoes press outwards against the drum, they try to turn a bit with the drum. This causes the front-most brake shoe to press against the adjuster screw assembly, which then presses against the rear-most shoe. And the rear-most shoe rotates up against the anchor pin up at the top. The net effect is that the two shoes "wedge" themselves against the drum, boosting braking effort.
As you press harder on the brake pedal, the Proportioning Valve first allows full Master Cylinder pressure to go to the rear drum brakes. But as pedal pressure increases, eventually you will hit the "split point" of the Proportioning Valve. After the split point is reached, the pressure into versus pressure out of the P.V. will no longer be a 1:1 ratio. For a further increase of pedal pressure, the rear line pressure will not increase as much. This limiting the increase in rear brakeline pressure avoids premature lock-up of the rear brakes due to the self-wedging action of drum brakes.
The front disc brakes, on the other hand, continue to get direct pressure, as they always work proportionally.
When releasing the brake pedal, the P.V. unseats, and allows brake fluid to return to the Master Cylinder so the rear shoes can retract.
I looked around to see if I still have a P.V. laying around. I can't find it. I have taken them apart, little plastic pieces like that cone you smashed, tiny passages, and some fine wire springs. They are precision parts.
Ten years ago they were ~ $90 USD at a Ford dealer.
Last edited by Torky2; Feb 23, 2008 at 12:50 AM. Reason: Corrected spelling typo
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Originally Posted by Torky2
Although I don't have a van, I have worked on large Ford cars which have a similar Master Cylinder and side-mounted Proportioning Valve. The side outlet with the Proportioning Valve goes to the rear drum brakes. The front outlet goes to the front disc brakes.
In disc brakes, the braking force is directly proportional to the applied hydraulic force acting on the piston in the caliper.
In drum brakes, as the hydraulic line pressure increases, a brake force multiplying factor occurs. As the two brake shoes press outwards against the drum, they try to turn a bit with the drum. This causes the front-most brake shoe to press against the adjuster screw assembly, which then presses against the rear-most shoe. And the rear-most shoe rotates up against the anchor pin up at the top. The net effect is that the two shoes "wedge" themselves against the drum, boosting braking effort.
As you press harder on the brake pedal, the Proportioning Valve first allows full Master Cylinder pressure to go to the rear drum brakes. But as pedal pressure increases, eventually you will hit the "split point" of the Proportioning Valve. After the split point is reached, the pressure into versus pressure out of the P.V. will no longer be a 1:1 ratio. For a further increase of pedal pressure, the rear line pressure will not increase as much. This limiting the increase in rear brakeline pressure avoids premature lock-up of the rear brakes due to the self-wedging action of drum brakes.
The front disc brakes, on the other hand, continue to get direct pressure, as they always work proportionally.
When releasing the brake pedal, the P.V. unseats, and allows brake fluid to return to the Master Cylinder so the rear shoes can retract.
I looked around to see if I still have a P.V. laying around. I can't find it. I have taken them apart, little plastic pieces like that cone you smashed, tiny passages, and some fine wire springs. They are precision parts.
Ten years ago they were ~ $90 USD at a Ford dealer.
In disc brakes, the braking force is directly proportional to the applied hydraulic force acting on the piston in the caliper.
In drum brakes, as the hydraulic line pressure increases, a brake force multiplying factor occurs. As the two brake shoes press outwards against the drum, they try to turn a bit with the drum. This causes the front-most brake shoe to press against the adjuster screw assembly, which then presses against the rear-most shoe. And the rear-most shoe rotates up against the anchor pin up at the top. The net effect is that the two shoes "wedge" themselves against the drum, boosting braking effort.
As you press harder on the brake pedal, the Proportioning Valve first allows full Master Cylinder pressure to go to the rear drum brakes. But as pedal pressure increases, eventually you will hit the "split point" of the Proportioning Valve. After the split point is reached, the pressure into versus pressure out of the P.V. will no longer be a 1:1 ratio. For a further increase of pedal pressure, the rear line pressure will not increase as much. This limiting the increase in rear brakeline pressure avoids premature lock-up of the rear brakes due to the self-wedging action of drum brakes.
The front disc brakes, on the other hand, continue to get direct pressure, as they always work proportionally.
When releasing the brake pedal, the P.V. unseats, and allows brake fluid to return to the Master Cylinder so the rear shoes can retract.
I looked around to see if I still have a P.V. laying around. I can't find it. I have taken them apart, little plastic pieces like that cone you smashed, tiny passages, and some fine wire springs. They are precision parts.
Ten years ago they were ~ $90 USD at a Ford dealer.
Thanks for the answer
very nice reading and easy understood as well
I realy need to find a new valve and seems like I need to put th eold master cylinder back on or getting the new replaced before 30 days ! (autorock) as this is going to smash my (if I ever find one) new valve !
we have absolutely nothing in DK , must order it from "over the pond" ;-)
Sincerly
JCBX
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